Slag skimmer



gApl 28,1925.

F. B. McKUNE SLAG S'KIMMEB 'Filed Feb, 26, 1924 5 Sheets-Sheet 2 April28, ,1925.

P. B. McKuNE SLAG SKIMMER Fild Feb. 26, 1,924 3 Sheets-Sheet 3 INVENTRATTORNEY Patented Apr. 28, 1925.

`UNITED STATES PATENT. OFFICE.

FRANK B. MCKUNE, on HAMILTON, ONTARIO, CANADA. f

VSLAG; SKIMMER.

Application filed February 26,1924. Serial No. 695,342.

, Skimmers, of which the following is a specification. t

In the practice of open hearth furnaces the' tapping hole is opened fromthe bot v tom. It is a diii'icult matter, however, to

control the size of the hole (depth and height of the hole) with theresult that the slag gets out `before all of the steel is Withdrawnfromthe furnace, hence the slag and steel, going into the ladle at thesame time, give rise, frequently, to bad boils. These boils are not onlydangerous but are.iesponsible for the loss in the additions, either putinto the furnace or into the ladle. This slag affects all of the alloysetc. which it is necessary to add to the heat before tapping and is,Without doubt, responsible for a great deal ofbadsteel (off heats). Y

. As the ladles for steel are brick lined the slag is responsible for alarge percent of the f Wear on` the brick Work (this Wear being mostnoticeable on the xstoppers, Which constitute one of the most importantparts of the ladle in 'controlling and pouring a heat) with the resultthat it is necessary `to rcline the ladle frequently.

`I have heretofore provided means With a view of overcoming theforegoing' difficulties, see for example my United `States application,Serial No. 590,486, led September 25, 1922, and my present invention hasfor its object to provide a simplified means for the purpose Which Willbe of less expense to .manufacture and install than the deviceheretofore designed by me.

In its general nature the present invention comprises a tapping troughleading` from the furnacerto the ladle and having` a lateral outletcooperating with a slag spout Which leads to the slag pot or pit, thevtapping trough being so mounted that its pitch may be varied to causemore or less material to flow through the lateral passage, therebymaking it possible to control the HOW in suoli Way that the slag can allbe run off through the lateral passage While the metal will pass to theend of the tapping trough and be delivered into the ladle.

In its more detail nature the invention includes those novel features ofconstruction,

combination and arrangement of paits, all

of which will be first fully described, and then be specifically pointedout in the appended claims, reference being had to the accompanyingdrawings, in which:

Figure lvisla plan .view illustrating the l invention.

Figure 2 isa side elevation, parts of the furnace structure and thesupporting platform being shown in cross section, illus trating in fulllines one position of the tapf ping trough and in dot and dash linesanother position of the same.

Figure 3 is a front elevation showing my invention and its `relation tothe ladle and slag pot.

Figure Ll is a detail cross section ofthe tapping trough showing amodified Way of mounting the same on the sling or cradle in the furnaceend. y V

` Figure 5 is a det-ail elevation of the sling or cradle' shown inFigures 1 to 3 inclusive, the tapping trough being indicated in dottedlines and the relation of the sling to the tap ping hole plate beingindicated in dotted f l lines. i

Figure 6 is a plan view of the structure shown in Figure 5. y

Figure 7 is a detail cross section on the line 7 7 of Figure 6.

Figure 8 is a detail the slag spout.

In the drawings in which like numerals perspective view of of refeiencedesignate likefparts in Vall the figures, l represents the front of thefurnace Which has the usual` tap hole 2 and to which the tap holecasting or plate 8 is mounted in the usual Way. 3 designates theplatform supporting beamsl which extend across the front of the furnace.

Securedb bolts rivets or in an other "i suitable Way, to thetap holeplate S is a sling or cradle composed of upright angle bars G secured toa transverse I beam t Vby connectng plates 7, there being a channelplate 5 secured to the I beam 4 in any suitable Way, on which channelplate is a short plate 9 with angle irons 10 spaced apart to receive orcradle that end of the tapping trough 11 which is held beneath the taphole spoutto receive the discharge from the furnace.

The tapping trough ll is of semicylindrical form and may be brick linedat 12 in the usual Way. It has a lateral branch or bypass 13 (seeFigures l to a inclusive), the

bottom of which is at a higher level than the bottom of the troughproper, the purpose for which will presently appear.`

The trough 11 may be provided with loops or other suitable devices 14 towhich the chain 15 that connects with the jib crane block 16 may connectso that by raising and lowering the block 16 by means of the crane thedischarge end of the trough 1l may be raised and lowered over the ladle22 to. cause the slag to pass out of the branch 13, while the metal isdelivered into the ladle.

The slag which passes out of the branch 13 is discharged into thereceiving end 18 of the slag spout 17 that conveys it to the slag pot 23or the slag pitas desired. The slag spout 17 is suspended at 20 from theI beams 3.

The receiving end of the trough 11 may be permitted to rest on theangles 10 on which the trough may have a rocking motion or pivotalmotion, although if desired the trough may be provided with trunnions 24that are mounted in bearings 25 on the channel irons 5.

The slag spout 17- has ears 19 to which the suspending members 20 arefixed. 21 designates the usual supports for the ladle 22.

In the practical application of my invention the tapping trough 11 islocated first in the dot and dash line position shown in Figure 2 sothat when the tap hole 2 is open the material will be sent rapidly tothe ladle 22. As the slag appears the trough 11 is raised until the slagis skimmed off into the lateral or branch 13 and is delivered into theslag spout 17. The more the slag is coming over the higher the front endof the trough 11 will be raised.

From the foregoing description, taken in connection with theaccompanying drawings, it is thought the complete construction, uses andadvantages of the invention will be clear to those skilled in the art.

It will be seen from the foregoing my arrangement provides a simple andinexpensive but effective means for accomplishing the desired object.

IVhat I claim is:

1. In apparatus of the class described, a tapping trough leading fromthe furnace to the ladle, said trough having a branch whose bottom is ata higher level than that 0f the trough proper, and means for pivotallyholding the trough in place wheieby its discharging end may be raisedand lowered to control the flow of metal through the ladle and slag intothe branch.

2. In apparatus of the class described, a tapping trough leading fromthe furnace to the ladle, said trough having a branch whose bottom is ata higher level than that of the trough proper, and means for pivotallyholding the trough in place whereby its discharging end may be raisedand lowered to control the flow of metal through the ladle and slag intothe branch, and a. slag spout leading from beneath the 'outlet of saidbranch to the slag pot.

3. In combination with the tap hole plate of a furnace, a sling securedto said plate, a tapping trough having one end located in said sling andits other end held to discharge into the ladle, and means for supportingthe discharge end of the trough to be raised and lowered, said troughhaving a lateral outlet branch adjacent the receiving end of the trough,the bottom of which outlet is at a higher level than that of the troughproper.

4. In combination with the tap hole plate of a furnace, a sling securedto said plate, a tapping trough having one end mounted pivotally in saidsling and its other end held to discharge into the ladle, and means forsupporting the discharge end of the trough to be raised and lowered,said trough having a lateral loutlet branch adjacent the receiving endof the trough, the bottom of which outlet is at a higher level than thatof the trough proper.

5. In combination with the tap hole plate of a furnace, a sling securedto said plate, a tapping trough having one end located in said sling andits other end held to discharge into the ladle, and means for supportingthe discharge end of the trough to be raised and lowered, said troughhaving a lateral outlet branch adjacent the receiving end of the trough,the bottom of which outlet is at a higher level than that of the troughproper, a slag spout extending from beneath said lateral outlet to theslag pit, and means to sustain the said spout in position to receive theslag from said lateral outlet.

FRANK B. MGKUNE.

